Video data is generally processed in the form of bit streams by video encoders and decoders (collectively “CODECs”), and stored on digital video disc (“DVD”) media. There is a substantial installed user base of red laser DVD players using MPEG-2 decoders. Red laser devices used with MPEG-2 encoding result in storage capacities sufficient to support standard-definition (“SD”) versions of typical movies, while there is great interest in supporting high-definition (“HD”) versions of these movies on the same disc. Unfortunately, the installed user base of red laser players used with MPEG-2 support a storage capacity insufficient for holding both SD and HD versions of typical movies.
Red laser and blue laser technologies have both been considered for reaching storage capacities sufficient to support high-definition recordings (“HD-DVD”). The blue laser technology has the advantage of providing sufficient storage to hold multiple high-quality HD movies on one disc using MPEG-2, but it is not yet economically feasible to use blue lasers to supplant the installed user base of red laser devices. Hence, there is a need for a coding scheme usable for HD-DVD that can also support SD-DVD on the same disc readable by current red laser devices using MPEG-2 decoders.
Thus, with red laser HD-DVD, it is desirable to store on a single disc, in addition to the HD version, an SD version of a movie that can be read by a current player having an MPEG-2 decoder. This would mean that content creators would not need to make a separate HD-DVD disc in addition to the SD disc, and retailers would need to stock only one disc per movie, using just one stock keeping unit (“SKU”). This may avoid problems such as those encountered with broadcast high-definition television (“HDTV”), where broadcasters did not want to transmit HD until more HD sets were sold, but consumers did not want to buy HD sets until there was more HD content available.
The present invention assumes the use of single-sided storage media. While double-sided discs are an option for obtaining more storage, there is some resistance to using both sides of the disc. This is due in part to the disadvantages of increased cost and of the fact that storing content on both sides interferes with the labeling that is normally put on one side of a disc. Accordingly, the approaches for HD-DVD of (i) blue laser technology; (ii) double-sided red laser discs; and (iii) separate red laser discs for HD and SD versions of a movie; each have significant drawbacks and disadvantages.